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Total Protein Content Determination of Microalgal Biomass by Elemental Nitrogen Analysis and a Dedicated Nitrogen-to-Protein Conversion Factor

  • L. M. L. LaurensEmail author
  • J. L. Olstad
  • D. W. Templeton
Part of the Methods in Molecular Biology book series


Accurately determining protein content is important in the valorization of algal biomass in food, feed, and fuel markets, where these values are used for component balance calculations. Conversion of elemental nitrogen to protein is a well-accepted and widely practiced method, but depends on developing an applicable nitrogen-to-protein conversion factor. The methodology reported here covers the quantitative assessment of the total nitrogen content of algal biomass and a description of the methodology that underpins the accurate de novo calculation of a dedicated nitrogen-to-protein conversion factor.


Amino acids Nitrogen analysis Nitrogen-to-protein conversion factor Protein 



This work was supported by the U.S. Department of Energy under Contract No. DE-AC36-08GO28308 with the National Renewable Energy Laboratory. Funding provided by U.S. DOE Office of Energy Efficiency and Renewable Energy Bioenergy Technologies Office. The U.S. Government retains and the publisher, by accepting the article for publication, acknowledges that the U.S. Government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this work, or allow others to do so, for U.S. Government purposes.


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Copyright information

© Springer Science+Business Media New York 2018

Authors and Affiliations

  • L. M. L. Laurens
    • 1
    Email author
  • J. L. Olstad
    • 1
  • D. W. Templeton
    • 1
  1. 1.National Renewable Energy LaboratoryNational Bioenergy CenterGoldenUSA

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